The present disclosure relates to a paper feeder configured to feed sheets and an image forming apparatus with the paper feeder.
As an example of a paper feeder operable to feed sheets, a paper feeder fitted in an image forming apparatus is known. The paper feeder is composed of a sheet cassette capable of being loaded into and unloaded from an apparatus body of the image forming apparatus, a pick-up roller, a paper feed roller, and a retard roller. The pick-up roller, the paper feed roller, and the retard roller are mounted to the apparatus body. The sheet cassette can contain sheets. When a lift plate mounted on the sheet cassette moves up, the uppermost of the sheets in the sheet cassette is pressed against the pick-up roller. Then, the pick-up roller is rotated, so that the sheet is fed in a sheet conveyance direction.
The sheet fed forward by the pick-up roller is introduced into a paper feed nip formed by the paper feed roller and the retard roller. With the rotation of the paper feed roller, the sheet is further conveyed downstream in the sheet conveyance direction.
When the sheet cassette is inserted hard into the apparatus body with sheets stacked in the sheet cassette, some of the sheets may enter the paper feed nip. In addition to this, if the sheet cassette is pulled out of the apparatus body with some sheets entering the nip in the apparatus body (in the event of multifeed failure), the sheets will be stuck in the apparatus body.
As a solution to the above problem, there is known a technique in which the movement of sheets in the apparatus body is restricted by an interlocking mechanism disposed across the sheet cassette and the apparatus body.